Grottenstelsel
Stargate Blue Hole
National Geographic gave the central shaft as about 340 ft (about 104 m) in 2010; the local operator describes depths of more than 330 ft (about 100 m) in some areas.
A deep inland fracture blue hole on South Andros with a central shaft of about 100 m and long passages running north and south. It lies on private family land and sits below a hydrogen sulfide layer that divers must pass through.
Stargate is an inland blue hole near the Bluff on South Andros, formed along a fracture in the island's limestone. A central shaft drops to roughly 100 m, and large passages lead away from it to the north and south. The cave was named by the British cave-diving pioneer Rob Palmer, and the entrance is on land held for generations by a local family.
The water surface lies a few metres below the rim, and divers enter with a stride from the edge. Below a fresh-water cap is a pale layer of hydrogen sulfide, produced by bacteria living below the fresh water, which some divers find causes nausea or headaches. Beneath it the cave opens into wide tunnels lined with flowstone and other formations.
Stargate is part of the South Bight fracture system, which also includes other deep inland blue holes. The guiding operator describes the South Andros blue holes as technically demanding caves, and Stargate is visited on organised trips with experienced guides.
Geologie
Stargate is a fracture cave: a long crack in the limestone platform that was enlarged by dissolution and decorated with speleothems while sea level was low, then flooded as sea level rose.
Water, stroming en overstromingen
National Geographic reported that a fresh-water lens on top of salt water blocks oxygen exchange, allowing bacteria in the layer below to produce hydrogen sulfide; the sulfide layer begins about 15 m below the surface.
Waarom het belangrijk is
Stargate was one of the blue holes studied during the 2009 National Geographic-funded Bahamas Blue Hole Expedition, which looked at microbes, fossils and climate records in Bahamian blue holes. Explorer Brian Kakuk pushed its North Passage and South Passage during that period.
Omstandigheden
A hydrogen sulfide layer lies below the fresh-water surface layer. The guiding operator runs trips to South Andros only in the cooler winter months.
Gebruikelijke ranges uit gepubliceerde bronnen, geen actuele omstandigheden.
Survey- en verkenningsgeschiedenis
| 2009 | Divers on the National Geographic Bahamas Blue Hole Expedition worked in Stargate; Brian Kakuk had explored the North Passage about 400 m from the shaft and pushed into the South Passage. [1] |
Ingangen en duiklocaties
One entrance, reached by a short walk from the road, on private land. Location given at area level only.
Voor oriëntatie, niet voor navigatie. Holle stippen zijn bij benadering.
Elk gegeven op deze pagina, met zijn bron (11)
| Gegeven | Status | Bron |
|---|---|---|
| Stargate's central shaft is about 340 ft (about 104 m) deep.National Geographic 2010; the operator says 'more than 330 feet in some areas'. | Gemeld | [1] [2] |
| Passages run north and south from the central shaft; the South Passage extends about 2,500 ft (about 760 m).2010 figures. | Gemeld | [1] |
| Rob Palmer named the cave, and the entrance lies on land held by Nikita Shiel-Rolle's family for generations.2010. | Gemeld | [1] |
| The water surface is about 20 ft (6 m) below the rim and divers enter with a giant stride; a crack at about 60 ft (18 m) leads to the north passage.Undated trip report from after 2010. | Gemeld | [3] |
| A hydrogen sulfide layer begins about 50 ft (15 m) below the surface and can cause nausea and headaches in some divers. | Gemeld | [1] |
| Stargate is a large inland fracture blue hole in the Bluffs area of South Andros, part of the South Bight fracture system with El Dorado Blue Hole and Rat Bat Lake.Provider description. | Gemeld | [2] |
| Brian Kakuk explored the North Passage about 1,300 ft from the central shaft and pushed into the South Passage.As reported in 2010. | Gemeld | [1] |
| The entrance is on private family land.2010; current arrangements not published. | Gemeld | [1] |
| The operator runs South Andros trips in the winter months only.Provider claim. | Gemeld | [2] |
| Area coordinates are those of The Bluff settlement on South Andros in the GeoNames gazetteer (24.1167, -77.55).Settlement-level only; the entrance is on private land and its exact location is not given. | Gemeld | [4] [2] |
| No landowner or official requirements are published; the Abaco-based operator offers Stargate on winter-only guided expedition trips.Provider claim. | Gemeld | [2] |
Geverifieerd: vermeld door een officiële of primaire bron die we hebben geraadpleegd. Gemeld: alleen afkomstig van een secundaire bron. Bronnen spreken elkaar tegen: de noot geeft beide versies. Mogelijk verouderd: de nieuwste bron die we hebben gevonden is oud.
In eigen woorden geschreven op basis van bovenstaande bronnen. Een correctie melden